<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        fetch('http://localhost/books/123',{
            method:'get'
        }).then(function(data){
            // text()方法返回一个Promise实例对象，用于获取后台数据
            return data.text()
        }).then(function(data){
            console.log(data)
        })
    </script>
</body>
</html>